Evaluation of the Effectiveness of a Biological Product Based on Saprophytic Bacteria and Natural Sorbents for the Rehabilitation of Oil-Contaminated Soils

Book DOI: 10.21467/abstracts.93 of which were selected experimentally. Previously has been shown that a strain of B. pumilus is avirulent, has a high enzymatic and adhesive ability, which made it possible to use it as a component of a biological product, as well as to create its immobilized form on glauconite granules [2]. We used an overnight culture of bacteria grown on meat-peptone ohm broth e (BCH) at 28o C. Glauconite is a clay mineral of variable composition with a high content of ferrous and trivalent iron, calcium, magnesium, potassium, phosphorus, as well as a number of trace elements [3]. All of them are in easily removable form of exchangeable cations, which are replaced by elements in excess in the environment. Due to these properties and the layered structure, glauconites are characterized by high sorption ability, including oil products. For research, the following samples were obtained: K control sample of soil containing oil products; P1A experimental sample containing 84 g of glauconite sorbent; P2B an experimental sample containing 84 g of the sorbent of glauconite and 1 ml of the broth culture of bacteria B. pumilus; P3A is an experimental sample containing 168 g of glauconite sorbent; P4B an experimental sample containing 168 g of the sorbent of glauconite and 1 ml of the broth culture of bacteria B. pumilus; P5 is an experimental sample containing 1 ml of a broth culture of B. pumilus bacteria. Results and discussion. Bytes ylo found that the concentration of oil in the initial sample of the soil was 2217 ± 10,4 mg / kg. The introduction of 84 g of the natural sorbent glauconite into the test sample led to a slight decrease in the concentration of oil products in the test soil sample. A two-fold increase in the mass of glauconite introduced contributed to a significant decrease in the mass concentration of oil products in the studied soil sample by 10.1 times in comparison with the control. The results obtained indicate the possible adsorption of petroleum products on the surface of granules of a natural sorbent. For the possible disposal of petroleum products contained in soil samples, bacteria B. pumilus were introduced into their composition . It was found that the exposure of soil samples with microorganisms within 30 days led to a decrease in the mass concentration of oil products by 10.3 times compared with the control. The highest efficiency was shown for the soil sample P4B. A decrease in the mass concentration of petroleum products by 14.9 times in comparison with the control was revealed. It is likely that the high intensity of a decrease in the concentration of petroleum products when B. pumilus is introduced into the samples both independently and in combination with glauconite granules indicates the hydrocarbon-oxidizing ability of this microorganism. Thus, it was found that the introduction into the soil samples contaminated with oil products of a strain of saprophytic bacteria B. pumilus, the natural sorbent of glauconite, as well as their combinations, contributed to a decrease in the mass concentration of pollutant. A direct dependence of the intensity of the decrease in the mass concentration of oil products on the mass of introduced glauconite has been established. The results obtained allow us to consider the combination of B. pumilus and glauconite as effective components of a biological product for the rehabilitation of soils contaminated with oil products.